In a slaughterhouse processing line, a hide is commonly removed from a carcass by a hide-pulling assembly such as a downpulling assembly. Typically, downpulling assemblies are used in processing lines wherein the carcass is suspended from a conveyor by its hind legs so that the longitudinal direction of the carcass is transverse to the path of the conveyor. The downpulling assembly pulls downwardly on the hide so that at least a portion thereof is detached from the carcass. The downpuller may remove the entire hide by pulling the hide over the carcass' head.
In some known downpulling assemblies, such as those disclosed in U.S. Pat. No. 4,299,860 and 3,737,949, an operator is required to engage the downpulling assembly with the hide. The assembly disclosed in the '860 patent employs a rotating skinning drum to which the hide is attached by a chain. One end of the chain is fixed to the drum and the operator attaches the other end of the chain to a hide portion. The hide is then wrapped around the drum as the drum rotates. Of course, the hide must be unwrapped from the drum before the next hide pulling operation, thereby slowing the processing line. The '949 patent discloses an assembly where an operator rides a carriage which moves with the carcass as the hide is pulled therefrom. The operator inserts a hide portion between a pair of counterrotating wringer elements which apply a pulling force effective to remove the hide. The carriage is moved downwardly along the back of the carcass during the hide pulling operation.
Assemblies which require an operator for engagement of the hide have a number of drawbacks. First, the operators are exposed to extremely dangerous working conditions. In order to remove the hides, the downpulling assemblies must be capable of generating great pulling force. Operators working in close proximity to these machines have suffered serious injuries including severed arms from entanglement with the machinery. Second, the use of an operator adds cost to the overall processing of carcasses. Thus, for safety considerations as well as cost reduction considerations, it is desirable to engage hides without manual implementation. Such a method and apparatus could, by reducing the manpower requirements of the slaughterhouse, also improve food-product hygiene.
Other known downpulling assemblies, such as that disclosed in U.S. Pat. No. 4,307,490, concentrate large pulling forces on a relatively small portion of the hide. In the '490 assembly, a portion of the hide is inserted between gripping jaws mounted on a shaft. The pulling force can then be exerted by driving the shaft downward. In such assemblies, the pulling force is concentrated on a relatively small portion of the hide increasing the likelihood of hide damage. It is desirable to eliminate damage because animal hides are commercially valuable products.
In addition, current downpulling assemblies may slow the processing line due to operator and equipment inefficiencies thereby limiting plant capacity. In some processing lines employing downpulling assemblies, the conveyor is stopped while the hide is pulled from the carcass. If the conveyor continued to move while a fixed downpulling assembly pulled on the carcass, lateral forces would be exerted on the conveyor. These lateral forces would place additional stress on the conveyor drive means and tend to cause components of the drive means to slip, e.g., a drive chain could slip on its sprockets or slippage could occur between gears.
None of the known downpulling assemblies solve the dangerous working conditions, hide damage, and line delay problems described above. Thus, there is a need for a method and apparatus for pulling hides from carcasses which greatly reduces dangerous working conditions, increases processing line speed and reduces the likelihood of hide damage.